Abstract: In order to discuss the influence of backfill width on deformation features of gob-side entry retaining roof, we take roadside filling at 5768 working face in Shenning Wulan Coal Mine as engineering background, and use MidasGTS numerical simulation and field measurement, study influence law of different width of backfill on deformation feature of entry retaining roof. results show that the determinated width by numerical simulation is small roof deformation with stable backfill after surrounding gradually stabilized, which shows that the backfill width is scientific and reasonable.